What does the atomic numbrr represent on the periodic table?

Explanation:

The atomic number tell us the number of protons and neutrons in the nucleus of an atom. in other words ,each element has a unique number that identifies how many protons are in one atom of that element example, all hydrogen atoms, and only hydrogen atoms, contain one proton and have an atomic number of 1.

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.